Safety device for elastic-fluid generators



June 19, 1928.

R. TROGER SAFETY DEYICE FOR ELASTIC FLUID GENERATORS Filed Oct. 7, 1926 Pig M ,7, I: a 3 a in ,l, 9 n w .2 M 4 d n i a "I a a a I MY IF-II" 0 W/ WM/J: f u I m H a W. n/ a Circulating Pump Steam Generator" Condenser" Prime Mover Inventor: Richard Trge-r His Attorneg.

Patented June 19, 1928.

UNITED STATES PATENT OFFICE.

TRGGEB, 0F IBEELIN-ZEHLENDOBF, GERMANY, ASSIGNOR, BY MESNE AS- SIGNMEN'ES, TO BAILEY METER. GOMPANY, A COMORATION OF DELAWARE.

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Application filed 0ctober 7, 1326, Serial No. 140,196, and in Germany October 23, 1825.

The present invention relates to elastic fiuid generators such as steam boilers, and has for its object generally to proivde an improved safety device/for such a generator,

a as hereinafter described.

F or a consideration of what I believe to be novel and my invention, attention is directed to the accompanying description and the claims appended thereto.

to In the drawing, Fig. 1 is a diagrammatic view of a boiler furnace provided with mechanism embodying the invention, and Fig. 2 is a diagram.

With elastic fluid boilers, such as steam 1ft boilers, it is generally usual to regulate the supply of combustibles, i. e. supply of fuel and air, according to the output demanded or according to an operating value related with the same, as, for example, the boiler pressure, either by hand or by means of automatic devices.

Fundamentally the manner of operation of a steam generator Working on a steam power plant may be regarded as of'a secondary circuit, which is represented by the circulation of steam and water, is dependent upon a primary circuit, which is represented by the supply of fuel and air. This relationship is diagrammatically illustrated in Fig. 2 in which i may represent the primary and H the secondary circuit of a steam generator 1, whose firing side receives air and fuel represented by the lines 2 and 3, and delivers smoke and gases and ashes represented by the lines a and 5, and whose steam side delivers steam through the line 6 to the prime mover 7 and receives water through a line 8 from the condenser 9 connected to the exhaust of prime mover v7, circulation, of the water being effected by the pump 10. It is readily seen that with automatic regulation, a mutual relation exists between the two circuits I and II. Variations in the primary circuit I not only cause corresponding variations of the secondary circuit but also vice versa, on account of the automatic regulation, a variation in the steam and water circulation will correspondingly afl'ect the operations in the primary circuit. This has the result that not only operating variations on the steam side cause a corresponding variation of the supply of fuel and air, but also disturbances, such as may be caused, for example, b pipe breakage or unforeseen load shocks. ereeither be mounted ,on the steam fore, if, for example, a steam pipe bursts, the regulator, on account of the increased flow of steam or the fall of pressure in the boiler, will act in the direction of increasing the firing, whereby the accident is, of course, made worse.

In the case of boilers regulated by hand, in which the automatic reaction on the primary side cannot take place, the breakage of a part or the boiler or a pipe under pressure has not the particularly disadvanta-. geous result of an increase in the supply of heat, but, nevertheless, even in this case, there exists the difiiculty that further firing often cannot be prevented, because, on account of the steam escaping, it is impossible to reach the devices for shutting ofi the supply of air and fuel.

More specifically, the object of the present invention is to provide an im roved regulating arrangement which. emhbdies means which comes into action automatically to shut down the boiler in the case of such disturbances. It is characterized essentially by the feature that a supervisory device for the output of the steam generator or for one of the operating values of ,the secondary circuit related with the-output, on a set maximum value being exceeded, acts on the firing operations in the primary circuit (for example, on the devices for supplying fuel or air) in the sense of a partial or complete throttling of the supply of heat. The supervisory device may be constructed electrically and act as a maximum relay, but the essence of the invention is not altered if the device is constructed as a maximum regulator, which throttles the supply of fuel and air of the primary side to such an extent that the set maximum value on the secondary side is not exceeded. The supervisory device may ipes proceeding from the boiler or on t esupply pipes leading to the boiler; ap' ropriately, however, the automatic action 0 the safety device is made dependent both on the steam as well as the water circulation.

0n the primary side that operatin value will be regulated which determines t e output of the boiler completely or partially; these are ingeneral the fuel supply, the air supply and the suction draught. These may be varied readily by actin on the driving pnlptors for the feed ng devices, fans and the Referring to Fig. 1 of the drawing, 11' indicates a boiler furnace which is supplied with pulverized fuel by means of a fuelfeeding device 12 operated by an electric motor 13, 14 indicatin the powdered fuel burner. Air is supplied to the furnace through a conduit 15 by means of a blower 16 driven by an electric motor 17. Water is supplied to the boiler through a pipe 18 and the steam generated flows from the boiler through pipe 19. The suction draught for the boiler is eifected by a suction fan 20 driven by an electric motor 21. Motors 13, 17 and 21 are connected to power lines 22 which receive electrical ener from a suitable source of power throug a switch 23.

Motors 13, 17 and 21 may be controlled manually or automatically in any suitable .manner to regulate the output of the boiler furnace in accordance with the demand, the specific manner for operating them not being shown, as 'it forms no part of the present invention. The arrangement so far described is to be taken as t pical of any suitable boiler furnace and ring arrangement therefor. t

In air inlet conduit 15 is arranged a normally open shut-off valve 24 which is biased toward closedpositionb a weight 25 connected to the valve by a exible connector 26' extendin over a pulley 27. Weight 25 is sup orte normally by an abutment 28 carrie by the plunger of a solenoid 29, and in this position of t e weight, valve 24 is open. In a similar manner, in the gas discharge conduit for the furnace, is a shut-01f valve '30 biased toward closed position by a weight 31 normally supported by an abutment 32 carried -b the plunger of a solenoid 33. Valve likewise is normally in 0 en posi tion. The windings'of the solenoi s 29 and 33 are connected in a suitable source of electrical energy 34, the circuit including a circuit closer comprising an adjustable contact plate 35 which is adapted to be engaged by either of two contacts 36 or 37, the circuit i being closed whenever either contact 36 or 37 engages contact plate 35. Contact 36 is carried by a lever arm 38 which is connected by a stem 39 to a flexible diaphragm 40 mounted in a fluid-tight casing 41. Casing 41 on opposite sides of diaphragm 40 is connected by pipes 42 and 43 to con uit 19 on opposite sides of a suitable ressure-difierence creating device 44. In t e present instance, pressure-difference creatin device 44 is shown as bein in the form 0 an orifice in a plate, this being a well-known type of pressuredifierence creating device. With this arrangement, as is well understood, diaphragm 40 is subject to a differential pressure which bears a definiterelation to the rate of flow of fluid through conduit 19 and the arrangement is such that when such rate of flow exceeds a predetermined maximum value the tact-plate 35. In a similar manner contact 37 is carried by a lever arm 45 whic is connected by a stem 46 to diaphragm 47 contained in casing 48. Casing 48 on opposite sides of the diaphragm is connected by pipes 49 and 50 to conduit 18 on o posite sides of pressure-diflerence creating evice 51 similar to pressure diflerence creatin device 44. With this arrangement, when 51c flow of fluid through conduit 18 exceeds a predetermined'maximum value, diaphragm 47 will be moved'so as to bring contact 37 into engagement'with contact late 35, thus closing the circuit on the windings of solenoids 29 and 33. The flow res onsive devices illus trated are shown only iagrammatically and by way of example and are to be taken as typical of any suitable arrangement for accomplishing the desired result. Connected to switch 23 is a solenoid 52 the winding of which is connected in parallel with the windings of solenoids 29 and 33. Switch 23 liquid to the boiler exceeds a predetermined maximum value, the circuits on the windings I i of solenoids 29, 33 and 52 will be closed.

simultaneousiliy, thereby opening switch 23 so as to cut 0 the sup lyof power to motors 13, 17 and 21 and at the same time releasing weights 25 and 31 to efiect theclosing of shut-ofi valves 24 and 30. i p 3 Under some circumstances, it will be desirable, in addition to the foregoing, to provide also valve means mounted in conduits 18 and 19, which valve means will be closed along with the operation of the other safety device. Whenever this is desired, it maybe accomplished in a manner similar to that already described in-connection with the de-. vices specifically illustrated, and for this reason further illustration is believed to be unnecessary. However, under such circumstances, the valve means in conduit 18 for the feed water supply should be placed only under control of the ressure responsive device 47 which respon s to the rate of flow of liquid in conduit 18 and should not be placed under control of the pressure responsive device 40.

In connect-ion with the claims,it is to be understood that by the term .combustible I mean either fuel or air, or both.

In accordance with the provisions of the Patent Statutes, I have described the prin ciple of operation of my invention, together with the a paratuswhich I now consider to. represent t s best embodiment thereof, but 1' desire to have it understood that the apparatus shown is only illustrative and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the United States, is

1. The combination with a boiler having means for supplying combustible thereto, of means responsive to the rate of flow of vapor from the boiler for shutting off the supply of combustible when the output of the boiler exceeds a predetermined maximum value.

2. The combination with a boiler having means for supplying fuel and air thereto and motors for driving such means, of means responsive to the rate of flow'ot' vapor from the boiler for disconnecting said motors from their energy sources when the output of the boiler exceeds a predetermined maximum value.

3. The combination with a boiler having means for supplying combustible thereto, of

means responsive to the rate of flow of Vapor from the boiler for shutting off the supply of combustible when the flow of vapor from the boiler exceeds a predetermined value. I

4. The combination with a boiler having means for supplying combustible thereto, of

means for shutting off the supply of combustible when the flow of liquid to the boilerexceeds a predetermined value.

5. The combination with a boiler having means for supplying fuel and air thereto and motors for driving such means, of means for disconnecting said motors from their energy sources when either the flow of vapor from or the flow of liquid to the boiler exceeds a predetermined value.

6. The combination with a boiler having means for supplying fuel and air thereto, motors for driving said means and a draft damper, of means for disconnecting said motors from their energy sources and for effecting closing of said damper when the boiler output exceeds a certain maximum va ne.

T. The combination with a boiler having means for supplying fuel and air thereto, motors for driving said means and a draft damper, of means for disconnecting said motors from their energy source and for effecting closin of the said damper when the flow of liquld to the boiler exceeds'a certain maximum Value. I

8. The combination with a boiler having means for supplying fuel and air'thereto, motors for driving said means and a draft damper, of means for disconnecting said motors from their 'energysource and for effecting closing of the said damper when the flow of liquid to or the flow of vapor from the boiler exceeds a certain maximum value.

In witness whereof, I have hereunto set my hand this QOthday. of Sept, 1926.

RICHARD TRoGER. 

